Bonding agent applications

Contamination of treated metal part before bonding agent application... 

N.B. The final stages of any wet metal preparation process for metals to be bonded to rubber is to ensure that all chemicals used in the processes have been removed in the final water rinse tank, and then to ensure that all faces of the metal parts are fully dried prior to bonding agent application. All warehouse metal storage areas must be held at least 5 -10 °C above the dew-point and ideally as near to ambient temperature in the bonding agent application shop which should be in the region of 18 - 22 °C minimum. 

Figure 3.5 Time sequence for bonding agent applications...

Waterborne bonding systems do not have the same ability as organic solvents to wet out the metal surface or solubilise any greasy contamination during bonding agent application to the metal surface. Another factor is quick evaporation of the alternative carrier from the applied adhesive film. Use of water requires higher temperatures for its removal from a deposited film of adhesive. Incomplete removal will result in porous adhesive layers, or even in underbond corrosion at the metal surface. 

Disadvantages include the problems of careful handling to prevent flocculation, and the higher heating costs from metal warm-up prior to and after bonding agent application. 

The bonding agent technique is usually not applicable to the metal particles in the composite. However, the surface of the metal is almost invariably covered by a thin (40-80 A) oxide layer [50]. The free energy of oxide surfaces is normally quite large (10 mJ/m ) to allow quick wetting by most organic polymers (40-60 mJ/m ). Additionally, the metal surface may provide two... 

The chemical composition of the composite constituents and the interphase is not limited to any particular material class. There are metal-matrix, ceramic-matrix, and polymer-matrix composites, all of which find industrially relevant applications. Similarly, reinforcements in important commercial composites are made of such materials as steel. E-glass, and Kevlar . Many times a bonding agent is added to the fibers prior to compounding to create an interphase of a specified chemistry. We will describe specific component chemistries in subsequent sections. 

High Alumina Refractories. The desired alumina content, from 100% to just above 45%, is obtained by adding bauxites, synthetic aluminosilicates, and synthetic aluminas to day and other bonding agents. These refractories are used in kilns, ladles, and furnaces that operate at temperatures or under conditions for which fireday refractories are not suited. Phosphate-bonded alumina bricks have exceptionally high strength at low to intermediate temperatures and are employed in aluminum furnaces. High alumina and mullite are used in furnace roofs and petrochemical applications. 

Surface oxidized before application of bonding agent... 

Bonding agent predried before reaching metal (spray application)... 

Reposition spray gun in relation to part Check bonding agent viscosity Add higher boiling diluent Increase time or temperature between application and bonding Ketone types usually responsible... 

In all such applications, the bonding surface must be correctly prepared, and the correct bonding agents must be used, allowed to dry, and, if needed, activated properly. 

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